• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.05a
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• pp.800-807
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• 2003

Decomposition of tasks in the ordinary manufacturing systems is usually based on the predefined goal of the system. To achieve the high-level-goals (e.g., factory goal or company goal), several sub-goals should be achieved in advance. However, goals can change along with the current status of the system and the external environmental situations. Thus, a manufacturing system should support the goal-formations which can be bearable these changes for efficient and effective operations. Therefore, it IS necessary to develop a systematic methodology for the goal-formations in a manufacturing system. Especially, the formation and/or change of goals in real-time should be possible for distributed and dynamic systems including the fractal manufacturing system (FrMS). In this paper, a threefold methodology is proposed for the goal-formation process (GFP) in the FrMS; 1) a goal­generating process (GGP) to make and propagate fuzzy goals, 2) a goal-harmonizing process (GHP) to eliminate or reduce conflicts and interferences of goals by using a mobile agent- based negotiation scheme, and 3) a goal-balancing process (GBP) to make a compromise between goals by using quantifiable indicators of the manufacturing system.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.12
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• pp.94-100
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• 2000

This paper presents a methodology for In-Process monitoring of tool wear by using ultrasonic sensor in turning operation. An integrated single ultrasonic transducer operation at a frequency of 10MHz is placed in contact with the insert tip. The change in amount of the reflected energy from the nose and flank of the tool can be related to the level of tool wear and the mechanical integrity of the tool. As the results, the tool wear monitoring system based on the ultrasonic pulse-echo method was proposed, it is useful to determine a tool life and tool change time.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1394-1397
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• 2003

The first thing in developing injection molding and extrusion with microcellular foaming process is to get a grip on one phase state's rheology of gas and polymer solution. Understanding rheology is essential to design mold or die. and it is so important to control the condition of process. Also, this data is got the utmost out of simulation carrying out. In this paper, we will see the measurement of rheology in one phase that mixed polypropylene which contains talc with carbon dioxide of super critical fluid state, and will compare its result with the simulation result.

• Journal of Educational Research in Mathematics
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• v.19 no.1
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• pp.143-161
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• 2009

This study was designed to gain insights into students' visualization process in geometric problem solving. The visualization model for analysing visual process for geometric problem solving was developed on the base of Duval's study. The subjects of this research are two Grade 9 students and six Grade 10 students. They were given 2D-geometric problems. Their written solutions were analyzed problem is research depicted characteristics of process of visualization of individually. The findings on the students' geometric problem solving process are as follows: In geometric problem solving, visualization provided a significant insight by improving the students' figural apprehension. In particular, the discoursive apprehension and the operative apprehension contributed to recognize relation between the constituent of figures and grasp structure of figure.

• Journal of the Korean Wood Science and Technology
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• v.39 no.3
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• pp.230-237
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• 2011

The study was performed to investigate the characteristics of charcoal and temperature change of a kiln's inner and outer walls in carbonization process using improved kiln. In this kiln system, carbonization process was completed in eight days. In the kiln, the ignition temperature was kept about $720^{\circ}C$. And then the temperature were increased gradually prior to be refined. Finally, the temperature in refining process was reached to maximum point, $1,000^{\circ}C$. In the chimney, the temperature was increased gradually from $90^{\circ}C$ at ignition to $750^{\circ}C$ at refining. The temperature change of the kiln wall resembles a temperature change progress curve during a carbonization process. The highest temperature of the kiln wall that appeared by a carbonization process was around $500^{\circ}C$. As a result of having measured an inner wall and the outer wall of the kiln using an infrared thermography camera, it was judged with there being considerable latent heat on kiln wall and ceiling. Fixed carbon contented of charcoal was 85.9~89.9%. Refining degree of charcoal, hardness, calorific value and pH were l, 12, 7,047~7,456 kcal/kg, 9.0~9.9, respectively. The yield of wood charcoal was 13.8%, and compared to conventional kiln's yield increased 1.5%.

• Particle and aerosol research
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• v.9 no.1
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• pp.1-6
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• 2013

New evaluation method for the particle size and morphology via change of ground particle during a grinding process was investigated. The grinding experiments were carried by a planetary ball mill. The relationship between the particle outline of the scanning electron microscopy photograph and measurement line, the measurement contact number was evaluated. The value of contact number decreased with the increase in the particle size of the ground sample, and varied with the experimental conditions. The value of contact number, which is related to the particle size of the raw sample, changed at the various experimental conditions.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.6
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• pp.807-813
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• 2012

Flocculation and flotation are used as pretreatment steps prior to the reverse osmosis (RO) process. During seawater treatment, high temperature can change the water chemistry of seawater during the process of coagulation. It also affects bubble volume concentration (BVC) and bubble characteristics. Coagulants such as alum and ferric salts at $40^{\circ}C$ can also change flux rates in the seawater reverse osmosis (SWRO) process. In this study, the bubble characteristics in dissolved air flotation (DAF), used as a SWRO pretreatment process, were studied in synthetic seawater at $20^{\circ}C$ and $40^{\circ}C$. The flux of an RO membrane was monitored after dosing the synthetic seawater with coagulants at different temperatures. Results showed that BVC increases as the operating pressure increases and as the salt concentration decreases. The bubble size released at $40^{\circ}C$ is far smaller than that at $20^{\circ}C$The addition of a ferric salt is effective for turbidity removal in synthetic seawater at $20^{\circ}C$; it is more effective than alum. When synthetic seawater was dosed with a ferric salt, the RO membrane flux increased by 27 % at $40^{\circ}C$.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.10a
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• pp.169-172
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• 2009

Multiple scale modeling has been applied to predict defect shape change during the wire rod rolling process. The size difference between bloom and defect prevent using usual FEM approaches due to the enormous number of elements required to depict the defect. The newly developed multiple scale model can visualize defect shape changes during the multi stands rolling process. The defect positioned at the top and side of bloom are smoothed out but the one at the middle evolved as folding or remained as crack. This approach can be used for defect control with roll shape design and initial bloom shape.

• Journal of Environmental Science International
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• v.9 no.1
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• pp.27-33
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• 2000

The purpose of this paper is to present the environment change of Cheju Island as land development process using GSIS(Geo-Spatial Information System) technique. We implemented the process based on the maps of soil color, underground water pollution points, land use, land development planning and land sight seeing supported by Cheju Province Office. To use the maps for GSIS data, first we transformed the picture data of the office into raster structured picture data using scanner. Second, the coordinate system was added to raster data using 1/50000 geographic map. Third, we estimated land planning process using GSIS technique(overlay and reclass technique). The results showed that land development effected the natural environment(forest, green field, farm land). However, the chemical pollution and land sight seeing was not so much effected by the land development that was found.

• Journal of Korean Public Health Nursing
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• v.30 no.1
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• pp.105-121
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• 2016

Purpose: This study examined the influencing factors from the Transtheoretical Model on the stage of change in the self-management behaviors, i.e. regular physical activity and diet, among community-residing adults with hypertension in a rural area. Methods: With a cross-sectional descriptive design, 134 adults who had registered and received a prescription for hypertension medication from a public health center in W city were recruited using convenient sampling. The instrument was an interviewer-administered questionnaire on the stage of change, process of change, self-efficacy, and decisional balance of physical activity and diet. The data were analyzed using descriptive statistics, 2-sample t-test, ${\chi}^2$ test, and logistic regression. Results: The results revealed significant differences in the process of change, self-efficacy, and decisional balance of physical activity and diet between those who were in the pre-execution stage (precontemplation, contemplation, preparation) and those who were in the execution stage (action and maintenance). Logistic regression showed that consciousness raising and self-efficacy were significant predictors of the execution stage in physical activity, and self-reevaluation, social liberation and self-efficacy were significant predictors in the diet. Conclusion: The relevant processes of change, differentiated according to the stage of change, along with self-efficacy, should be addressed to enhance the execution of self-management behaviors among hypertensive adults residing in the community.